1. Field of the Invention
The subject invention relates to suction pipes or aspirators and, more particularly, to aspirators for textile machines or yarn drawing equipment.
2. Information Disclosure Statement
For a long time, textile yarn drawing equipment for spinning machines has been equipped with aspirators for maintaining the working parts clean and for removal of torn threads. In this respect, cylindrical suction pipes have been employed and have been associated at their front end or suction opening with a cylinder of the drawing works, while being connected at their opposite rear end with an air pressure sink or pumping arrangement. Since the cross-section of such suction pipes is chosen to be as narrow as possible, in order to maintain low air consumption, while the torn threads are, however, only picked up reliably in the projected extension of the suction opening, part of the material to be removed is not apprehended by the available suction.
In an effort to enlarge the range of action without enlargement of the cross-section of the suction pipe, it has already been proposed to utilize a suction pipe with triangular cross-section. One edge of the suction opening of that suction pipe is arranged in parallel to the axis of the cylinder serving as guiding surface for the air stream, whereby the air is aspired primarily from that cylinder. Since such triangular configuration is, however, aerodynamically unfavorable and in particular causes the formation of eddy currents or turbulence, that known cylindrical suction pipe has adjacent its suction opening a constricted cross-section changing into an enlargement for improved aerodynamics. However, that known suction pipe is strongly subject to clogging and a removal of threads causing such congestion is rather cumbersome.